Russia on Tuesday activated a pipeline carrying Russian gas to Crimea with President Vladimir Putin hailing it as a step that would power economic growth on a peninsula Moscow annexed from Ukraine in 2014.
Crimea has no land border with Russia, and Moscow has struggled to meet its energy needs, which were previously met by Ukraine.
Putin, who watched the launch of the pipeline via a video link, said: "It is another very important solution for the long-term development of Crimea."
Moscow is also building a road and rail bridge to the peninsula and this year completed an electricity link. Crimea had suffered sporadic blackouts after unidentified individuals blew up power cables from Ukraine in November last year.